package com.sky.service.impl;

import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.List;

@Service
public class ShoppingCartServiceImpl implements ShoppingCartService {

    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private DishMapper dishMapper;
    @Autowired
    private SetmealMapper setmealMapper;

    /**
     * 添加购物车
     * @param shoppingCartDTO
     */
    @Override
    public void addShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        //判断数据库（购物车）里是否已经拥有相应的菜品和套餐
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        shoppingCart.setUserId(BaseContext.getCurrentId());  // 设置用户的id确保购物车唯一
        // 动态sql判断数据库里是否已经拥有相应的菜品和套餐
        List<ShoppingCart> list =  shoppingCartMapper.list(shoppingCart);
        //  如果有，就在数量上加一就OK
        if(list != null && list.size()>0){
            ShoppingCart shoppingCart1 = list.get(0); // 获取第一条数据实际上只有0和1一条两种情况
            // 数量加上1
            shoppingCart1.setNumber(shoppingCart1.getNumber()+1);
            shoppingCartMapper.updateNumberById(shoppingCart1);
        }else {  // 没有就添加一条新的数据，但首先得判断加入的是套餐还是菜品
            Long dishId = shoppingCartDTO.getDishId();
            if(dishId != null){ //这里代表接收的数据为菜品,则插入菜品数据
                //根据菜品id查询菜品信息
                Dish dish = dishMapper.getById(dishId);
                shoppingCart.setName(dish.getName());
                shoppingCart.setImage(dish.getImage());
                shoppingCart.setAmount(dish.getPrice());
            }else { // 不是菜品就应该插入套餐
                // 根据套餐id查询套餐信息
                Setmeal setmeal = setmealMapper.getById(shoppingCartDTO.getSetmealId());
                shoppingCart.setName(setmeal.getName());
                shoppingCart.setImage(setmeal.getImage());
                shoppingCart.setAmount(setmeal.getPrice());
            }
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartMapper.insert(shoppingCart);
        }
    }

    /**
     * 查看购物车
     * @return
     */
    @Override
    public List<ShoppingCart> showShoppingCart() {
        // 根据当前用户id来查询购物车。
        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = ShoppingCart.builder()
                .userId(userId)
                .build();
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        return list;
    }

    /**
     * 清空购物车
     */
    @Override
    public void deleteShoppingCart() {
        // 根据当前用户id来删除全部购物车。
        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = ShoppingCart.builder()
                .userId(userId)
                .build();
        shoppingCartMapper.deleteByUserId(shoppingCart);
    }

    /**
     * 减少一个产品
     */
    @Override
    public void reduce(ShoppingCartDTO shoppingCartDTO) {
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        //设置查询条件，查询当前登录用户的购物车数据
        shoppingCart.setUserId(BaseContext.getCurrentId());

        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        if(list != null && list.size() > 0){
            shoppingCart = list.get(0);

            Integer number = shoppingCart.getNumber();
            if(number == 1){
                //当前商品在购物车中的份数为1，直接删除当前记录
                shoppingCartMapper.deleteById(shoppingCart.getId());
            }else {
                //当前商品在购物车中的份数不为1，修改份数即可
                shoppingCart.setNumber(shoppingCart.getNumber() - 1);
                shoppingCartMapper.updateNumberById(shoppingCart);
            }
        }

    }
}
